Many types of footwear, in particular those for athletic use, often become wet when used. This is particularly true of ski boots which not only are externally exposed to snow and ice, but are of plastic so that the user's feet often sweat excessively. Thus after use, as at the end of a day's skiing, the user must dry the boots out overnight before they can be used again. This presents little problem for a person with his own equipment, as packing the boots with dry paper or the like and placing them in a warm location so they can dry properly represents a modest maintenance for the often relatively expensive foot gear.
When, however, such footwear, hereinafter referred to generically as boots, is not used by one person, as in a shop which rents such equipment, this maintenance is onerous and indeed often impossible. Thus at the end of the day's skiing the renting agency at the ski slope normally is left with hundreds of pairs of wet boots which must be dried out before they can be rerented early the next day.
The standard solution to this has been simply to set the boots out in a warm location at which is provided a heater and normally even a blower so that overnight sufficient air will be circulated on and around the stacked boots to dry them. In reality this procedure is often ineffective, as the amount of moisture that must be driven off the boots is frequently considerable, and stacking the boots up merely leads to the moisture from one dripping onto the other so that the lowermost boots are never properly dried.
Furthermore in a commercial large-scale operation it is not only essential for economic reasons to reduce the labor envolved in preparing the boots for rerenting, but it is also essential to sanitize the boots as much as possible. Low-grade foot infections and the like can easily be transmitted from one user to another of a pair of rented boots, in paticular when such boots are not completely dried and aired out. In fact the health risk involved in renting footwear often deters many customers, in particular when there is doubt that a properly maintained and sanitized boot can be rented.